Talk:Proton emission

Proton Emission in Carbon-14 formation?
According to other wiki pages, Carbon-14 is formed by thermal neutron (0.025 eV) absorption by the nucleus of Nitrogen-14 and the emission of a proton. Is this also considered a beta decay proton emission, or is there some other process involved? What is the energy of the emitted proton?Kenny56 08:04, 7 January 2006 (UTC)

Reading about Carbon-14 formation there is one question: as you said C14 is formed by thermal absorption by the N14 nucleus. 1 p+ is emitted. Okay, but that leaves 1 electron (e-). My question: is the emission of a proton always accompanied by Beta-radiation? So another question: what about the assertion that there is no proton radiation under natural circumstances? Baalu 22:26, 15 June 2006 (UTC)

Coulumb barrier?
For a proton to escape a nucleus, the proton separation energy must be negative - the proton is therefore unbound, and tunnels through the Coulomb barrier in a finite time.

Doesn't the proton have to tunnel thru the nuclear strong force barrier, not approach another nucleus's Coulomb barrier? --Vuo 01:46, 1 November 2006 (UTC)

The proton is already unbound in terms of the nuclear force, and is being held in place by the Coulomb barrier of the nucleus (and a centrifugal barrier if the proton is carrying orbital angular momentum). I know this isn't immediately intuitive, as we think of the Coulomb barrier in the first instance as something that repels external positive charges from the nucleus rather than being able to hold positive charges inside the nucleus. The following diagram illustrates the point: http://personal.ph.surrey.ac.uk/~phs1wc/CD-sirius/science/scigif6.gif (a nucleon is unbound if it is above the zero potential line in this diagram - the shape of the potential is a sum of the nuclear force, producing the below-zero well containing nuclear bound states, and the Coulomb and centrifugal forces which produce the long above-zero tail) ---158.180.64.10, January 2007


 * That picture (accessible by the wayback machine) of the barrier for a proton (for different amounts of orbital momentum) does not really explain why the barrier has that shape nor how it differs from neutrons. No..


 * A slightly better explanation is Ch.I.5 of "Theoretical Nuclear Physics" by Blatt & Weisskopf (1979). They begin by saying yes, in general if we compare a proton and a neutron with the same amount of energy at the surface of a light nucleus, the proton is ejected more easily. (But since the proton gets a kick as it moves away from the nucleus, if we compared a proton and neutron which ultimately escaped with the same energy, then the neutron must have had more energy when it was in the nucleus. Conversely, there definitely was a Coulomb barrier deflecting protons from getting into the nucleus in the first place, which is why slow/thermal neutrons are more easily injected.) But in larger nuclei, from arguments pertaining to beta stability, they assert "The protons are more strongly bound by the nuclear forces in order to compensate..".


 * Question becomes, how does the nuclear force bind protons differently than neutrons (in these circumstances where the protons and neutrons differ in number)? Doesn't the residual strong force treat nucleons equally? Cesiumfrog (talk) 02:35, 3 December 2012 (UTC)

Iron-45
Should that be iron-54? Man with two legs 20:25, 30 March 2007 (UTC)

No, it really is Iron 45. A very exotic (and short-lived) nucleus!

Non-isotopes?
Lutetium-151 and Thulium-147 are so far from the stable masses of 175 and 169 respectively, that I question whether those are real. Dragons flight (talk) 19:42, 23 December 2007 (UTC)
 * If they were not that far, would they be dripping protons? (Almost nine years late, but it seems to me that others might have the same question.) Double sharp (talk) 03:54, 19 June 2016 (UTC)

Proton emission and cluster decay
Is proton emission a form of cluster decay, the emitted proton being a hydrogen-nucleus?

In the table in the Radioactive decay article, the definition of cluster decay seems to include proton emission ("nucleus emits a specific type of smaller nucleus..."), but the Cluster decay article defines cluster decay in terms of clusters of protons and neutrons! Eroica (talk) 08:07, 9 January 2008 (UTC)


 * A proton is not a nucleus, it is a nucleon. So no, it's not a cluster, and none of the articles cited say anything contradictory.  DAID (talk) 04:57, 18 July 2012 (UTC)